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Re: [TLS] Call for acceptance of draft-moeller-tls-downgrade-scsv

Kurt Roeckx <kurt@roeckx.be> Thu, 23 January 2014 18:07 UTC

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Date: Thu, 23 Jan 2014 19:07:13 +0100
From: Kurt Roeckx <kurt@roeckx.be>
To: Eric Rescorla <ekr@rtfm.com>
Message-ID: <20140123180713.GA31076@roeckx.be>
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Cc: "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] Call for acceptance of draft-moeller-tls-downgrade-scsv
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On Thu, Jan 23, 2014 at 11:06:04AM +0100, Eric Rescorla wrote:
> WG Members,
> 
> This message is a call for acceptance of
> http://tools.ietf.org/html/draft-bmoeller-tls-downgrade-scsv-01
> 
> As a TLS WG item.
> 
> Please provide any comments on this action by Feb 7.

I think preventing downgrade attacks is important, and as such
I think it's a good idea.  But I have to wonder if it actually
solves anything or not.

I think the document starts from the assumption that there is
someone in the middle that can alter the data, and then let the
client do a downgrade.  What is stopping this attacker from
removing this scsv from the client hello?


Kurt

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